The high prevalence, morbidity and mortality of osteoporosis in women offers a unique opportunity for investigation into the pathogenesis and prevention of this problem during the phase of rapid bone loss occurring in the immediate years following menopause. The primary objective of this study is to demonstrate the efficacy of omega-3 fatty acids in preventing loss of bone mass in an at risk population. We hypothesize that post-menopausal women who decline hormone replacement therapy and, thus, are at increased risk for loss of bone mass will have no bone loss on omega-3 fatty acids nutrient supplementation compared to similar women in a placebo control group. To better understand the mechanism of omega-3 fatty acids in preventing loss of bone mass, there are two secondary objectives: One is to examine the impact of omega-3 fatty acids on markers of bone turnover and the second is to examine the impact of omega-3 on cytokine production. We further hypothesize that omega-3 fatty acids will decrease loss of bone mass in post-menopausal women by decreasing bone turnover, mainly by decreasing bone resorption.